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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Radiofrekvensidentifiering (RFID) : Vilka faktorer påverkar utvecklingen negativt?

Karlsson, Anders, Bengtsson, Mattias January 2006 (has links)
Radiofrekvensidentifiering (RFID) är en teknik som har funnits en längre tid men aldrig fått något riktigt genombrott på marknaden. Intresset för tekniken finns, men användandet har inte tagit fart. Anledningen till detta examensarbete är att ta reda på vad detta beror på. Uppsatsen har två syften där huvudsyftet är att undersöka vilka faktorer som har påverkat utvecklingen av RFID negativt, därefter ett bisyfte som är att undersöka hur framtiden för RFID ser ut. Undersökningen genomförs med hjälp av litteratur samt intervjuer av två respondenter, som använder sig av RFID i sitt arbete. Den ena respondenten utvecklar RFID lösningar till andra företag, medan den andra respondenten arbetar som forskare. För att komma fram till en slutsats jämför vi litteratur med de uppgifter som kommit fram genom intervjuerna. På detta sätt identifieras ett antal faktorer, som bromsar utvecklingen av RFID. De faktorer som framkommer delar vi in i marknadsfaktorer och tekniska faktorer. Marknadsfaktorerna är ointresse för tekniken, otillräckliga nätverkseffekter samt en långsam adoption av tekniken. Tekniska faktorer är kostnad, brist på gemensam standard, svårigheter i frekvensval samt säkerhetsaspekter.
192

Risk Analysis of the applied RFID system : Project Stolpen

Grunzke, Richard January 2007 (has links)
This thesis will be a risk analysis of a RFID-system for a logistical application. The system works as follows: Around Karlstad in Sweden there are three new weighing machines for lorries. The load weight will be measured for the police to control overweight and for logistical reasons such as issuing invoices and optimising the supply chain. The lorries do not have to stop to be weighed. They have to drive slowly over the weighing machine, so the loss of time is minimal. The lorries will be identified via RFID-tags. So every time a lorry will be driven over the weighing machine, the identification number and the measured weight will be logged and send to a database. In the future it is planed to store the weight on the tag itself. The task is now to analyse the RFID-communication and the transmission to the database. The thesis will contain several parts. First RFID in general and how RFID will be used in the application-scenario will be described. Next sections will be about the security and privacy requirements and the risks in detail. Then possible solutions are outlined and concrete suggestions are presented. Finally a conclusion will be drawn, which will show that the application has a low level of security.
193

Étude et conception d'antennes miniatures et directives à polarisation circulaire pour lecteurs RFID UHF / Study and design of circularly polarized miniature and directive antennas for UHF RFID readers

Pflaum, Sylvain 24 June 2013 (has links)
La technologie RFID fait dorénavant partie intégrante de notre quotidien. Les applications correspondantes à cette technologie sont des plus en plus nombreuses et répandues. Ce manuscrit a pour ambition la recherche de solutions innovantes pour lecteurs RFID UHF. Ce travail ayant été accompli dans le cadre du projet PACID Textile, les champs d’application de nos recherches ont été l’amélioration de la gestion, de la traçabilité et de la sécurité des textiles industriels et commerciaux de par des performances accrues des structures antennaires. Pour cela, l’antenne lecteur, entre autre, doit être miniature tout en étant faible coût, directive et à polarisation circulaire dans la bande RFID UHF (0,865-0,868 GHz). Les deux verrous technologiques principaux auxquels nous avons été confrontés pour l’antenne lecteur sont la gestion de sa direction de propagation privilégiée permettant de restreindre et maîtriser la zone de lecture ainsi que son encombrement afin de l’intégrer facilement dans n’importe quel environnement. Pour répondre à cette problématique, les axes de recherche abordés dans ce manuscrit ont été : L’obtention de la polarisation circulaire à l’aide de résonateurs à courts-circuits. L’étude et la conception d’antennes à base de métamatériaux de type BIE (Bande Interdite Electromagnétique) afin d’améliorer la directivité des antennes imprimées de par les propriétés originales de ces structures. La recherche de nouvelles techniques de miniaturisation des antennes imprimées par introduction d’un nouveau plan de masse de type BIE. / RFID technology is now a part of our daily lives. The corresponding applications are more and more numerous and widespread. This work having been done in the framework of the PACID textile project, this thesis has the ambition to research innovative solutions for RFID readers in order to enhance the management, the traceability and the security of the industrial and commercial textiles.Towards this end, the antenna reader has to be miniature while being low-cost, directive and in circular polarization in the RFID UHF band (0.865-0.868 GHz). The two main technological challenges that we have faced for the reader antenna is managing its main direction of propagation to restrict and control the reading zone as well as the miniaturization of its size in order to easily integrate it into any environment. To respond to this problem, the research areas discussed in this manuscript were: The obtaining of the circular polarization using short-circuited resonators. The study and design of microstrip antennas based on EBG (Electromagnetic Band Gap). Type metamaterials to improve their directivity by using the original properties of these structures. The research of new miniaturization techniques for printed antennas by introducing a new EBG ground plane.
194

Open Platform Semi-Passive Ultra High Frenquency Radio Frequency Identi

Li, Tzu Hao January 2011 (has links)
Radio frequency identi cation (RFID) is a rapidly emerging technology that enables au- tomatic remote identi cation of objects. Passive and semi-passive RFID systems can be distinguished from other forms of wireless systems, because the RFID tags (transponders) communicate by way of backscatter. In addition, passive tags derive their energy from the RF energy emitted by the reader. RFID technology can provide a fully automated data capture and analysis system. Compared to a passive RFID system, an open platform semi-passive UHF RFID tag can provide identi cation, security, low-power (compared to a wireless sensor net- work(WSN)), medium range and medium processing speed. However, the eld of semi- passive RFID is still under development, and has yet there are no open development platforms available. This thesis develops a prototype of a semi-passive UHF RFID tag that is compatible with the leading UHF RFID standard EPCglobal Gen 2 Class 1. I alsot has the exible I2C and analog digital converter(ADC) interface, which allows the additional of external analog and digital sensors. The sensor data can be read by microcontroller and stored at memory. Standard reader can get sensor data by sending QUERY and READ command to tag. Test results of our open platform semi-passive UHF RFID tag demonstrated that it can achieve a read rate above 50% when an open platform semi-passive UHF RFID tag is placed four meters from the reader antenna and the reader output power is set to 21 dBm. In addition, the proposed semi-passive open platform RFID tag consumes very little power (4.9 mA in 2V with system frequency set to 8MHz).
195

Next Generation RFID Randomization Protocol

LaValley, Jason January 2011 (has links)
Radio Frequency IDentification (RFID) is a wireless communications technology which allows companies to secure their assets and increase the portability of information. This research was motivated by the increased commercial use of RFID technology. Existing security protocols with high levels of security have high computation requirements, and less intensive protocols can allow a tag to be tracked. The techniques proposed in this thesis result in the increase of ciphertexts available without a significant increase in processing power or storage requirements. The addition of random inputs to the generation of ciphertexts will increase the number of possible results without requiring a more advanced encryption algorithm or an increased number of stored encryption keys. Four methods of altering the plaintext/ciphertext pair (random block, set pattern, random pattern, and indexed placement) are analyzed to determine the effectiveness of each method. The number of ciphertexts generated, generation time, and generation errors were recorded to determine which of the four proposed methods would be the most beneficial in a RFID system. The comparison of these method characteristics determined that the set pattern placement method provided the best solution. The thesis also discusses how RFID transmissions appear to attackers and explains how the random inputs reduce effectiveness of current system attacks. In addition to improving the anonymity of RFID tag transmissions, the concept of authenticating random inputs is also introduced in this thesis. These methods help prevent an adversary from easily associating a tag with its transmissions, thus increasing the security of the RFID system.
196

Evaluating Tangible User Interface-based Mobile-learning System for Young Children

Albalawi, Rania January 2013 (has links)
Recently, young children’s educational behavior has become a popular topic for researchers seeking to help develop their skills and abilities in a pleasurable manner. Lately, we have seen the emergence of several communicational units that include powerful and advanced technologies, such as mobile devices. In fact, according to a CISCO report, ‘in 2012 the numbers of mobile-connected devices in circulation are greater than the number of people on earth. By 2016 there will be 1.4 mobile devices per capita, and there will be over 10 billion mobile-connected devices, including (M2M) modules, exceeding the world's population at that time (7.3 billion)’ [1]. In this thesis, we introduce a mobile-based edutainment system called ‘Tap and Learn’ that targets young children and aim to assist them in developing their learning abilities and social communication skills. The Tap and Learn system allows children to learn about new objects and entities in their environments by simply tapping over them with a RFID-mounted smart phone which responds by producing a set of multimedia feedback that aims to foster their learning skills in an entertaining manner. The M-learning system does not require y special tools or environments to be operated and required minimal literacy levels. In addition,, the system enable the parents to participate in their children's learning by allowing them to personalize the learning material and the media content of the games so they suit their children's cognitive level and their learning wants.
197

Localization and Proximity Detection in the Internet of Things Based on an Augmented UHF RFID System

Rostamian, Majed January 2014 (has links)
In the "Internet of Things" (IoT), the things will be able to sense, communicate, and interact. They will also exchange data, information and knowledge, and locate themselves and other things that surround them. In order to be able to interact, the things need to recognize that they are in proximity of other things. It is anticipated that the most widespread components of the IoT will be passive radio frequency identification (RFID) tags because they are inexpensive and provide automatic identification. However, passive RFID tags are not capable of performing complex operations, such as proximity detection and localization, which will be required in future networks. In this thesis, we describe existing problems with current RFID systems and survey potential solutions for localization and proximity detection. Then we present a new RFID device called "Sense-a-Tag" (ST) that can passively detect and decode backscattered signals from tags in its proximity. There have already been an attempt to use this device for tracking. However, detailed analysis of the performance of the ST especially for proximity detection has not been performed yet. We show that when STs are added to a standard RFID system, the problems of proximity detection and localization with RFID tags can readily be solved. Then we applied ST-based system for identifying people and object interactions. The potential uses of ST as an augmented device for IoT applications are discussed in this thesis. Advantages and limitations of an ST based RFID system have been investigated in details for each application. Results obtained from real experiments illustrate that an ST-based RFID system is feasible for proximity detection applications. In addition, a special software is developed in C\# to process the data and run a localization algorithm based on proximity detection information. The same software has been used for tracking people's activity. Different scenarios have been considered in the experiments. We tried to consider majority of factors that might affect the accuracy in the experiments including: angle and distance between the reader/ST and tags, timing in sending queries, presence of human body, etc. The simulations based on real experiments and results illustrates that an ST-based RFID system can be a realistic solution for proximity detection and localization for Location Positioning systems (LPS) and activity monitoring in future IoT.
198

Algoritmy pro zpracování a analýzu RFID signálu v FPGA / Algorithms for analysis and processing of RFID signals in FPGA

Harvánek, Michal January 2015 (has links)
The result of this thesis is the architecture design for a software-defined radio, which is used to analyze the signal emitted by RFID tags in real time. The aim of this analysis is to measure the frequency characteristics of the RFID tag. The main means for achieving the objective of optimizing signal processing algorithms and reduce the time needed to control the hardware compared to the classical concept of SW radio USRP. It is described how to obtain and display digitally sampled signals using a graphical programming language LabVIEW and subsequent processing of these data in MATLAB. Further described is the skeleton of the proposed solution.
199

Radio Based User Presence

Santamaría Portolés, Ana Rosalía January 2015 (has links)
While radio frequency identification tags (RFIDs) have been widely used for identifying objects (and some people), their primary use has been for access control, inventory, and other similar purposes. In this thesis we will use the detection of an RFID to indicate that a user is present in a given location.  This will be used to extend a Session Initiation Protocol (SIP) system with user presence. A typical HF RFID reader is able to read a tag from a range of 8-10 cm. In this application we wish to read tags from a range of 50 to 100 cm (the width of a doorway or narrow hallway). One of the challenges is how to increase the reading range while staying below the maximum RF power limits (for reasons of safety). Providing an RFID based presence indication can be used to automatically adjust the heating, ventilation, and air conditioning system of a room, etc. This thesis presents several different antennas which were analyzed and simulated using FEKO to obtain a suitable antenna for this target application. The thesis shows that fractal patterns are the best for the intended application based upon the results of simulations. These antennas were implemented and tested. The prototype establishes that such antennas are a suitable design and can be used with current RFID systems to achieve long ranges. The thesis also suggests some future enhancements to these antennas. / Identifiering av radiofrekvenstaggar (RFID) har använts i stor utsträckning för att identifiera objekt (och vissa människor). De primära användningsområdena har varit åtkomstkontroll, inventering, och andra liknande ändamål. I denna avhandling kommer vi att använda närvaroupptäckten av en RFID-tagg för att ange att en användare befinner sig påen given plats. Detta kommer att användas för att utöka ett Session Initiation Protocol-system med användarnärvaro. En typisk HF RFID-läsare kan läsa en tagg från ett avstånd av 8-10 cm. I denna appliceringen vill vi läsa RFID-taggar från ett avstånd av 50 till 100 cm (bredden påen dörröppning eller en smal korridor). En av utmaningarna är hur man kan öka läsavståndet och samtidigt hålla sig under de maximala RF-effektgränserna (av säkerhetsskäl). En RFIDbaserad närvaroindikering kan användas för att automatiskt justera värme, ventilation och luftkonditionering av ett rum, osv. I denna avhandling kommer vi att presentera olika antenner som analyserades och simulerades med hjälp av FEKO, för att erhålla en lämplig antenn. Avhandlingen visar att de bästa resultaten från simuleringarna för det huvudsakliga målet, är att använda fraktala mönster. Genomförandet och testerna av dessa antenner leder till en prototyp av en gynnsam antennutformning, som en bas för framtida förbättringar. Dessutom beskriver vi skälen till varför fraktalantenner ofta används i nuvarande RFID-system för att uppnålånga läsavstånd.
200

Bluetooth vs RFID in Time Tracking

Berndtsson, Fredrik January 2017 (has links)
Bluetooth and Radio Frequency Identification (RFID) are two technologies which are used in lots of contexts today, for example Bluetooth is used for communication between devices and RFID as identification of items at storehouses. This work contains a comparison between those two technologies in a time tracking environment for sports events. To compare the two technologies, a Bluetooth time tracking prototype based on Raspberry Pi 3 and Android Sony Xperia M5 were developed to be compared with a preexisting RFID timing system. The work has been done at Blekinge Institute of Technology in Karlskrona. An agile project form has been used in the work containing a prestudy, development, verification, experimentation and survey phase. The survey focused on smartphones for timing, and the experiments were qualitative. Three of the questions that have been answered during the work are, if Bluetooth could be used in a timing context, what are the difference in reading performance at different speeds and distances. In both unobstructed and blocked Bluetooth can be read at longer distances. Both systems can read tags at 30 kilometers an hour close to the readers. / Bluetooth och Radio Frequency Identification (RFID) är två vanliga teknologier som användsi stor utsträckning idag, till exempel Bluetooth används för bland annat kommunikation mellan enheter, medans RFID används bland anatt för identifiering av objekt i lagerlokaler. Detta arbetet jämför teknologierna utifrån ett tidtagnings perspektiv för olika idrottslopp. För jämförelsen mellan teknologierna utvecklades en Bluetooth tidtagnings prototyp baserat på en Raspberry Pi 3 och en smartphone applikation, och för RFID användes ett redan utvecklat tidtagningssystem. Arbetet har utförts på Blekinge Tekniska Högskola i Karlskrona. Ett iterativt arbetssätt hara nvänts under arbetes gång innefattande en förstudie, utveckling, verifikation, experiment ochen enkätfas. Enkäten fokuserade på smartphones för tidtagning och experimenten som utfördes var av kvalitativ karaktär. Två av forskningsfrågorna som blivit besvarade under arbetet är om Bluetooth kan användas för tidtagning och om det går, vad är skillnaden på prestandan i låga respektive höga hastigheter på olika avstånd? Några av resultaten från arbetet är att i fri sikt kan Bluetooth bli läst på längre avstånd än RFID. Båda systemen kan läsa av taggar upp till 30 kilometer i timmen nära läsaren.

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